How severe is CVE-2018-18439?

CVE-2018-18439 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-18439 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-18439?

CVE-2018-18439 primarily affects Denx U-boot. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-18439?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2018-18439 published?

CVE-2018-18439 was published on 2018-11-20 and last updated on 2026-06-17.

CVE-2018-18439

CVE-2018-18439 is a critical-severity vulnerability in Denx U-boot with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-119.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-119
Affected product: Denx U-boot
Published: 2018-11-20
Last modified: 2026-06-17

Description

DENX U-Boot through 2018.09-rc1 has a remotely exploitable buffer overflow via a malicious TFTP server because TFTP traffic is mishandled. Also, local exploitation can occur via a crafted kernel image.

Frequently asked questions

What is CVE-2018-18439?: DENX U-Boot through 2018.09-rc1 has a remotely exploitable buffer overflow via a malicious TFTP server because TFTP traffic is mishandled. Also, local exploitation can occur via a crafted kernel image.
How severe is CVE-2018-18439?: CVE-2018-18439 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-18439 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-18439?: CVE-2018-18439 primarily affects Denx U-boot. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-18439?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2018-18439 published?: CVE-2018-18439 was published on 2018-11-20 and last updated on 2026-06-17.

References

http://www.openwall.com/lists/oss-security/2018/11/02/2

Affected products (2)

cpe:2.3:a:denx:u-boot:*:*:*:*:*:*:*:*
cpe:2.3:a:denx:u-boot:2018.09:rc1:*:*:*:*:*:*

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